/*常用的初始化样式*/

body {
    width: 100%;
    max-width: 640px;
    min-width: 320px;
    margin: 0 auto;
    font-size: 14px;
    font-family: -apple-system, Helvetica, sans-serif;
    line-height: 1.5;
    color: #666666;
}

ul {
    margin: 0;
    padding: 0;
}

li {
    list-style: none;
}

a {
    text-decoration: none;
}


/* 去除图片的空白缝隙 */

img {
    vertical-align: middle;
}

.app {
    height: 45px;
}

.app ul li {
    float: left;
    height: 45px;
    background-color: #333333;
    text-align: center;
    line-height: 45px;
}

.app ul li:nth-child(1) {
    width: 8%;
}

.app ul li:nth-child(1) img {
    width: 10px;
}

.app ul li:nth-child(2) {
    width: 10%;
}

.app ul li:nth-child(2) img {
    width: 30px;
    /* 行内块默认是基线对齐 改成居中对齐 */
    vertical-align: middle;
}

.app ul li:nth-child(3) {
    width: 57%;
    color: white;
}

.app ul li:nth-child(4) {
    width: 25%;
    background-color: #f30420;
    color: white;
}

.search {
    position: fixed;
    height: 44px;
    background-color: #c6001f;
    text-align: center;
    line-height: 44px;
    color: #ffffff;
    min-width: 320px;
    max-width: 640px;
    width: 100%;
    /* 解决外边距合并的问题 */
    overflow: hidden;
}

.search-btn {
    position: absolute;
    top: 0;
    left: 0;
    width: 40px;
    margin: 0px 0px 0 5px;
}

.search-btn img {
    width: 20px;
    height: 18px;
}

.search-input {
    margin: 0 50px;
    height: 30px;
    border-radius: 15px;
    border: 1px solid #ffffff;
    background-color: #ffffff;
    /* 外边距合并 给父级添加hidden */
    margin-top: 7px;
}

.search-login {
    position: absolute;
    top: 0;
    right: 5px;
    width: 40px;
}

.search-input img {
    width: 20px;
    height: 15px;
    position: absolute;
    top: 16px;
    left: 66px;
    background: url('../img/jd.png') no-repeat;
    background-size: 20px 15px;
}

.search-input .line {
    content: "";
    position: absolute;
    left: 92px;
    top: 16px;
    display: block;
    width: 1px;
    height: 15px;
    background-color: #cccccc;
}

.search-input .search-icon {
    height: 15px;
    position: absolute;
    left: 100px;
    top: 16px;
    width: 18px;
    background-color: #cccccc;
    background: url('../img/jd-sprites.png') no-repeat -81px 0;
    background-size: 200px;
}

.main-content img {
    width: 100%;
}

.brand {
    overflow: hidden;
    border-radius: 10px 10px 0 0;
}

.brand div {
    float: left;
    width: 33.33%;
}

nav a {
    float: left;
    width: 20%;
    text-align: center;
}

nav a img {
    width: 40px;
    height: 40px;
    margin: 10px 0;
}

nav a span {
    display: block;
    color: #333333;
}

.two a {
    width: 50%
}

.two a img {
    float: left;
    width: 47%;
    margin-top: 10px;
}

.two a:nth-child(1) img {
    margin-left: 10px;
}

.two a:nth-child(2) img {
    margin-right: 10px;
}

.one img {
    margin-top: 10px;
    width: 100%;
}

.fadeIn img {
    width: 100%;
}

.book {
    float: left;
    width: 50%;
    box-sizing: border-box;
}

.book img {
    width: 60px;
    height: 60px;
    margin: 5.5px 15px 0;
}

.book span {
    margin: 5.5px 20px 0;
}

.book span:nth-child(1) {
    display: block;
    font-size: 16px;
    font-weight: bold;
    color: blue;
}

.book span:nth-child(2) {
    display: block;
    font-size: 12px;
    color: #666771;
}

.four {
    float: left;
    width: 25%;
    margin-top: 20px;
}

.four span {
    margin-left: 20px;
}

.four img {
    width: 60px;
    height: 60px;
    margin: 5.5px 15px 0;
}

.four span:nth-child(1) {
    display: block;
    font-size: 16px;
    font-weight: bold;
    color: #000000;
}

.four span:nth-child(2) {
    display: block;
    font-size: 12px;
    color: #666771;
}